docs: def assert_less_equal(first, second, msg_fmt="{msg}"):
      """Fail if first is not less than or equal to second.
  
      >>> assert_less_equal('bar', 'foo')
      >>> assert_less_equal(5, 5)
      >>> assert_less_equal(6, 5)
      Traceback (most recent call last):
          ...
      AssertionError: 6 is not less than or equal to 5
  
      The following msg_fmt arguments are supported:
      * msg - the default error message
      * first - the first argument
      * second - the second argument
      """
  
      if not first <= second:
          msg = "{!r} is not less than or equal to {!r}".format(first, second)
          fail(msg_fmt.format(msg=msg, first=first, second=second))